Fish Oil Doesn't Cut Failure Rate of Hemodialysis Grafts

TUESDAY, May 1 -- Taking fish-oil supplements does not significantly lower the failure rate of grafts used for hemodialysis, a new study finds.

The study included about 200 North American kidney-failure patients with a synthetic tube grafted between an artery and a vein, which provides access to the bloodstream for hemodialysis, a process in which waste products are removed from the blood.

The patients were randomly assigned to take fish-oil capsules or a placebo daily for one year, starting one week after the graft was created.

During that time, there was no statistically significant difference between the two groups in the proportion of grafts that failed to remain open, according to researchers at the University of Toronto and Toronto General Hospital.

Patients taking fish oil were less likely to develop blood clots, however, and went a longer time without developing blood clots. The fish-oil group also had a lower rate of radiological and surgical interventions.

The study appears in the May 2 issue of the Journal of the American Medical Association.

The patients in the study had an arteriovenous graft, which was the leading method for gaining vascular access among hemodialysis patients in North America in the early 1990s, according to the study.

But that type of graft fell out of favor due to its high complication rates and associated costs. It has been suggested that omega-3 fatty acids found in fish oils might help prevent arteriovenous graft complications.

These findings do not support this theory, an expert wrote in an editorial that accompanied the study.

Instead, another type of graft -- arteriovenous fistula -- is the preferred method, wrote Dr. Bradley Dixon, of the University of Iowa in Iowa City.

"However, if a patient cannot obtain a fistula and requires a graft, use of fish oil and an antiplatelet agent appears reasonable, pending the results of further studies," Dixon wrote.

More information

The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about hemodialysis.